ConvertXtoDVD - no audio on conversion

Hi there

Vista Home Premium 2.4GHz

I want to convert avi files to DVD to watch them on the home TV. I’m trying different software before I buy and I’ve had a few problems.
Vista closes down DVD Flick as soon as I try to load a film for conversion (and it doesn’t even bother to ‘go online for a solution’) so I’ve given up.
DIKO could not get the aspect ratio correct in any setting (it seemed to like 200:100) so now I’m using the trial version of ConvertXtoDVD but I don’t get an audio track when playing back on a TV, though it works fine on the PC - sound and vision. I’ve tried DVD-RW and DVD+R
Any thoughts?